From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Brody Beckwith <brody@beckwith.dev>
Date: Fri, 14 Jan 2022 00:41:11 -0500
Subject: [PATCH] Multi Block Change API Implementation


diff --git a/src/main/java/net/minecraft/network/protocol/game/ClientboundSectionBlocksUpdatePacket.java b/src/main/java/net/minecraft/network/protocol/game/ClientboundSectionBlocksUpdatePacket.java
index 82ea4fabd5732052a286d50bcff8bbcc2c4aa7d7..652bea6868a03a5315965f79c76172fb9dbb93fb 100644
--- a/src/main/java/net/minecraft/network/protocol/game/ClientboundSectionBlocksUpdatePacket.java
+++ b/src/main/java/net/minecraft/network/protocol/game/ClientboundSectionBlocksUpdatePacket.java
@@ -54,6 +54,15 @@ public class ClientboundSectionBlocksUpdatePacket implements Packet<ClientGamePa
 
     }
 
+    // Paper start
+    public ClientboundSectionBlocksUpdatePacket(SectionPos sectionPos, it.unimi.dsi.fastutil.shorts.Short2ObjectMap<BlockState> blockChanges, boolean suppressLightUpdates) {
+        this.sectionPos = sectionPos;
+        this.positions = blockChanges.keySet().toShortArray();
+        this.states = blockChanges.values().toArray(new BlockState[0]);
+        this.suppressLightUpdates = suppressLightUpdates;
+    }
+    // Paper end
+
     @Override
     public void write(FriendlyByteBuf buf) {
         buf.writeLong(this.sectionPos.asLong());
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
index 148e1985017f6955267b5c970730645394d700f6..43d96760828e4c9683398f3f6925701d003556e4 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
@@ -30,6 +30,7 @@ import javax.annotation.Nullable;
 import net.minecraft.Util;
 import net.minecraft.advancements.AdvancementProgress;
 import net.minecraft.core.BlockPos;
+import net.minecraft.core.SectionPos; // Paper
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.network.FriendlyByteBuf;
 import net.minecraft.network.chat.ChatType;
@@ -836,6 +837,35 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         this.getHandle().connection.send(packet);
     }
 
+    // Paper start
+    @Override
+    public void sendMultiBlockChange(Map<Location, BlockData> blockChanges, boolean suppressLightUpdates) {
+        if (this.getHandle().connection == null) return;
+
+        Map<SectionPos, it.unimi.dsi.fastutil.shorts.Short2ObjectMap<net.minecraft.world.level.block.state.BlockState>> sectionMap = new HashMap<>();
+
+        for (Map.Entry<Location, BlockData> entry : blockChanges.entrySet()) {
+            Location location = entry.getKey();
+            if (!location.getWorld().equals(this.getWorld())) continue;
+
+            BlockData blockData = entry.getValue();
+            BlockPos blockPos = new BlockPos(location.getBlockX(), location.getBlockY(), location.getBlockZ());
+            SectionPos sectionPos = SectionPos.of(blockPos);
+
+            it.unimi.dsi.fastutil.shorts.Short2ObjectMap<net.minecraft.world.level.block.state.BlockState> sectionData = sectionMap.computeIfAbsent(sectionPos, key -> new it.unimi.dsi.fastutil.shorts.Short2ObjectArrayMap<>());
+            sectionData.put(SectionPos.sectionRelativePos(blockPos), ((CraftBlockData) blockData).getState());
+        }
+
+        for (Map.Entry<SectionPos, it.unimi.dsi.fastutil.shorts.Short2ObjectMap<net.minecraft.world.level.block.state.BlockState>> entry : sectionMap.entrySet()) {
+            SectionPos sectionPos = entry.getKey();
+            it.unimi.dsi.fastutil.shorts.Short2ObjectMap<net.minecraft.world.level.block.state.BlockState> blockData = entry.getValue();
+
+            net.minecraft.network.protocol.game.ClientboundSectionBlocksUpdatePacket packet = new net.minecraft.network.protocol.game.ClientboundSectionBlocksUpdatePacket(sectionPos, blockData, suppressLightUpdates);
+            this.getHandle().connection.send(packet);
+        }
+    }
+    // Paper end
+
     @Override
     public void sendBlockDamage(Location loc, float progress) {
         Preconditions.checkArgument(loc != null, "loc must not be null");